The invention relates generally to wireless telemetry systems and more particularly to medical telemetry systems for monitoring patients in a hospital.
Patients in a hospital are monitored to obtain physiological data, such as body temperature, pulse rate, heart rate, blood pressure, oxygen saturation, respiratory rate, electrocardiography (ECG or EKG), electromyography (EMG), and electroencephalography (EEG). Wireless medical telemetry systems may be used to perform such monitoring. In wireless medical telemetry systems, a remote telemeter attached to the patient sends the patient's vital physiological data to a monitoring station over a wireless telemetry link. This allows the patient to move around in the hospital as the patient is not tethered to a wire-line telemetry system.
Large hospitals typically need to monitor a large number of patients simultaneously. Generally, large hospitals employ distributed antenna architecture for monitoring the large number of patients. However, this implementation suffers from high noise floors resulting from combining the large number of antenna outputs.
Another method employed by hospitals is cellular medical telemetry network. Cellular medical telemetry networks enhance the monitoring capacity of the medical telemetry system using techniques such as frequency reuse in Frequency Division Multiple Access (FDMA) networks. In FDMA networks, frequency reuse entails the allocation of the same time/frequency resources to mobile transmitters within more than one coverage area. Thus, the maximum number of telemeters in each cell is limited by the frequency channels allocated to the cell. Borrowing frequency channels from neighboring cells partly addresses this shortcoming, although at the expense of depleting the frequency channel capacity of neighboring cells. The movement of a large number of patients into a cell neighborhood, at the same time, may result in service interruption for some patient telemeters. Service interruption in the cellular medical telemetry network is a critical problem and may result in life-threatening events going unreported.
Also, different monitoring systems generate different amounts of data and may require different data transmission rates. Therefore, integration of different monitoring systems may necessitate separate infrastructure for different data transmission rates which may add to the complexity of the wireless medical telemetry system, and/or further compound the problem of limited frequency channels.
As a result, there is a need in the art for methods and systems for overcoming the aforementioned drawbacks associated with present wireless medical telemetry systems.